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<p class="header"><a class="header" href="intro.htm">Orbiter</a> &gt; <a class="header" href="mainmenu.htm">Main menu</a> &gt; Object information</p>

<h1>Object information</h1>

<p>Use the object information window to retrieve data and current parameters about</p>

<p><ul>
<li>the current camera target object</li>
<li>spacecraft</li>
<li>spaceports</li>
<li>celestial objects (sun, planets moons)</li>
</ul></p>

<p>The object information window can be opened during the simulation by selecting <i>Object info</i> from the main menu, or by pressing <kbd class="ctrl">Ctrl</kbd> <kbd>I</kbd>.</p>

<h2>Vessel information</h2>

<p>Select object type <i>Vessel</i>, and pick one of the spacecraft in the current simulation from the list. The information sheet for spacecraft and orbital stations contains:</p>

<p><ul>
<li>current mass</li>
<li>size</li>
<li>mass-normalised principal moments of intertia (PMI)</li>
<li>transponder frequency</li>
<li>equatorial position (longitude and latitude) above the celestial body the vessel is orbiting</li>
<li>altitude</li>
<li>ground speed</li>
<li>attitude relative to local horizon (yaw, pitch, roll angles)</li>
<li>orbital elements in the ecliptic frame of reference, relative to currently orbited planet </li>(semi-major axis, eccentricity, inclination, longitude of ascending node, longitude of periapsis, mean longitude at epoch)</li>
<li>docking port status, if applicable (free/docked vessel, instrument docking system [IDS] transmitter frequency)</li>
<li>time propagation mode (free-flight/landed, dynamic or stabilised time step updates)</li>
</ul></p>

<h2>Spaceport information</h2>

<p>Select object type <i>Spaceport</i> and pick one of the available surface bases from the list. Spaceport information sheets contain:</p>

<p><ul>
<li>planet/moon and equatorial position</li>
<li>landing pad status (free/landed vessel, and instrument landing system [ILS] transmitter frequency)</li>
<li>Runway information (runway alignment direction, length, and ILS transmitter frequency)</li>
<li>Frequencies of any VOR (very high frequency omnidirectional radio) transmitters associated with the spaceport</li>
</ul></p>

<h2>Celestial body information</h2>

<p>Select object type <i>Celestial body</i> and pick one of the bodies listed.
Information sheets for celestial bodies (such as sun, planets and moons) contain:</p>

<p><ul>
<li>physical parameters:</li>
<ul>
<li>mass (M)</li>
<li>mean radius (R)</li>
<li>length of siderial ("star") day (Ts)</li>
<li>obliquity of ecliptic (Ob) - tilt of axis of rotation against plane of ecliptic</li>
</ul>
<li>atmospheric parameters (if applicable):</li>
<ul>
<li>atmospheric pressure at zero altitude (p0)</li>
<li>specific gas constant (R)</li>
<li>ratio of specific heats c<sub>p</sub>/c<sub>v</sub> (g)</li>
</ul>
<li>orbital elements in the ecliptic frame of reference, relative to currently orbited body (semi-major axis, eccentricity, inclination, longitude of ascending node, longitude of periapsis, mean longitude at epoch)</li>
<li>current ecliptic position in polar coordinates (longitude, latitude and radius) relative to currently orbited body.</li>
<li>geocentric celestial position (right ascension and declination)</li>
</ul></p>

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